1. Field
Example embodiments relate to a non-volatile memory device, and for example, to a non-volatile memory device including a sensing transistor with a higher threshold voltage.
2. Description of Related Art
Non-volatile memory devices capable of electrically erasing and programming may store data even if a power source is not applied thereto. Non-volatile memory devices may be flash memory.
Flash memory is a device storing data using a charge storage. Each memory cell forming the flash memory is formed of a cell transistor including a control gate, a charge storage layer, a source, and a drain. The flash memory adjusts an amount of charge stored in the charge storage layer to change values of data written on the memory cells.
If a charge is injected into the charge storage layer of the cell transistor, the threshold voltage of the cell transistor increases. If a charge is erased from the charge storage layer of the cell transistor, the threshold voltage of the cell transistor decreases.
A state where the charge storage layer has a negative charge and the threshold voltage of the cell transistor is negative (e.g., minus) is referred to as an erase state. A state where the charges are injected into the charge storage layer and the threshold voltage of the cell transistor is larger than 0 is referred to as a program state.